ks4 the periodic table (boardworks)

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KS4 Chemistry

The Periodic Table


The Periodic Table

Patterns of behaviour

Patterns and electron structure

Elements and atomic number

Summary activities

Arranging elements

Contents


What are all substances made of?

…to gold, an unreactive metal.

From chlorine, a poisonous gas…

From sodium, a reactive metal…

There are millions of different substances in the world, but what are they all made of?

Elements – the building blocks of all substances.

There are about 100 different elements in a variety of forms.

…to oxygen, a life-giving gas.


Properties of elements

What is a property of an element?

A property is any characteristic of an element.

For example, here are some properties of sodium:

It would be really useful to be able to predict properties of elements instead of having to remember them!

Are there any patterns in the properties of elements?

metallic;

highly reactive;

solid but melts easily;

feels light (low density).


Properties and atomic number

The properties of an element depend on its atomic number.

What is the atomic number of an element?

Atoms contain three types of particles:

Where are these particles found in an atom?

Particle Mass Charge

proton 1 +1

neutron 1 0

electron almost 0 -1

atomic number = the number of protons in an atom


What is atomic number?

What are the particles in this helium atom?

What is the atomic number of helium?

neutron

proton electron

2


Atomic number, charge and electrons

Atoms contain equal numbers of protons and electrons.This means that atoms are neutral.

What links atomic number and the number of electrons?

9 protons = +99 electrons = -9

Total charge = 0

10 neutrons = 0

What is the charge of a fluorine atom?

atomic number = the number of electrons in an atom


Atomic structure revisited


The Periodic Table




Summary activities

Arranging elements

Contents


Periodic table timeline


Atomic number and patterns of behaviour

H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K

reactive metals

unreactive gases

reactive gases

If the elements are arranged in order of increasing atomic number, patterns in their properties can be seen.


Positions of similar elements

How many elements from one reactive metal to the next?

How many elements from one reactive gas to the next? 8

8

Compare the positions of similar elements:


How many elements from one unreactive gas to the next? 8

reactive metals

unreactive gases

reactive gases


Mendeleev and the periodic table

Mendeleev created the first modern periodic table by grouping together elements with similar properties.


Arranging elements

Arrange these rows so elements with matching properties are together:

Divide the elements at set intervals into separate rows:


cut here cut here cut here

H He

Li Be B C N O F Ne

Na Mg Al Si P S Cl Ar

K


Arranging elements into columns

When elements are arranged according to their properties what patterns do you see?

Similar elements go into the same columns.

Hydrogen is an exception – it is best positioned above the reactive metals.

He

Li Be B C N O F Ne


K

H

reactive metals reactive gases unreactive gases

hydrogen is a special case


The periodic table

Arranging all the elements by their atomic number and their properties led to the creation of…

…the periodic table

Fr Ra Ac Rf Db Sg Bh Hs Mt Ds Rg ? ? ? ? ? ? ?

Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn

Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe

K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr


Li Be B C N O F Ne

H He


Missing elements!

In this periodic table the symbols are replaced by atomic numbers. Some of the numbers are missing – where?

They are called the lanthanides and actinides and are only shown on some periodic tables.

87 88 89 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118

55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86

37 38 39 40 41 42 43 44 45 46 47 38 49 50 51 52 53 54

19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

11 12 13 14 15 16 17 18

3 4 5 6 7 8 9 10

1 2Two more rows of elements fit here.


The elements in the periodic table


Columns of elements

What are columns of elements called?

groups



Rb Sr Y Zr NbMo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe



Li Be B C N O F Ne

H He

1 2 43 5 6 07


Rows of elements

periods

What are rows of elements called?






Li Be B C N O F Ne

H He1

2

3

4

5

6

7


The Periodic Table




Summary activities

Arranging elements

Contents


Patterns: metals and non-metals

on the right (except hydrogen)

Where are these different types of elements grouped together in the periodic table?

metals

non-metals

between metals and non-metalsmetalloids

on the left and centre

Can you name a metalloid element?

Metalloids aren’t a type of rock music fan!

Metalloids have some properties similar to metals and other properties similar to non-metals.


Metals, non-metals and metalloids


Patterns: physical state

Only two elements are liquids at room temperature.What are they?

liquids

Where are these elements of different states grouped together in the periodic table?

in the middle and on the right

solids

on the far right (except hydrogen)gases

on the left, in the centre and on the right

bromine and mercury


Solids, liquids and gases


Patterns: reactivity of metals

Fr Ra Ac Rf Db Sg Bh Hs Mt Ds Rg

Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po

Rb Sr Y Zr NbMo Tc Ru Rh Pd Ag Cd In Sn

K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga

Na Mg Al

Li Be

What happens to the reactivity of metals down a group?

Which is the most reactive metal?

increase in reactivity

incr

ease

in

rea

ctiv

ity

What happens to the reactivity of metals along a period?


Which metal is more reactive?


Patterns: reactivity of non-metals

increase in reactivity

Group 0 elements are the most unreactive of all elements.

For the remaining non-metals and metalloids, reactivity increases up a group and along a period from left to right.

Which is the most reactive non-metal/metalloid?

At Rn

Sb Te I Xe

Ge As Se Br Kr

Si P S Cl Ar

B C N O F Ne

He

incr

ease

in

rea

ctiv

ity

unreactive


Which non-metal is more reactive?


The Periodic Table




Summary activities

Arranging elements

Contents


Patterns, atomic number and electrons

What links atomic number and the properties of elements?

The periodic table shows that patterns in the properties of elements are linked to atomic number.

electrons






Li Be B C N O F Ne

H He


Atomic number and electrons

atomic number = number of protons

atomic number = number of electrons

The properties of elements are hugely influenced by the number and arrangement of electrons in the atom.

What links atomic number and the number of electrons in an atom?

As atomic number increases by one, the number of electrons also increases by one.

This means that the elements in the periodic table are also arranged in order of the number of electrons.

number of protons = number of electrons


Electron shells

Electrons are arranged in shells around an atom’s nucleus.

This electron arrangement is written as 2,8,8.

1st shell holdsa maximum of

2 electrons

2nd shell holdsa maximum of

8 electrons

3rd shell holdsa maximum of

8 electrons

Each shell has a maximum number of electrons that it can hold. Electrons will fill the shells nearest the nucleus first.


Electrons in period 1

Elements in period 1 only have electrons in the first shell.

Why are there only two elements in period 1?

The first shell can only hold a maximum of two electrons,so period 1 only includes the elements hydrogen and helium.

What is special about the outer shell of helium?

1 2

H He

1 2 43 5 6 07

1



Elements in period 2 all have a complete first shell.

The second shell is completed one electron at a time going across the period from left to right.

What is special about the outer shell of neon?

2,1 2,2 2,3 2,4 2,5 2,6 2,7 2,8

Li Be B C N O F Ne

1 2 43 5 6 07

What happens to electrons in the second shell in period 2?

2



2,8,1 2,8,2 2,8,3 2,8,4 2,8,5 2,8,6 2,8,7 2,8,8

Elements in period 3 have complete first and second shells.

The third shell is completed one electron at a time going across the period from left to right.

What happens to electrons in the third shell in period 3?


1 2 43 5 6 07

What is special about the outer shell of argon?

3


Patterns of electron arrangements

Consider the electron arrangements of the first 20 elements in the periodic table.

What is the pattern of outer shell electrons in a group?

2,8,1 2,8,2 2,8,3 2,8,4 2,8,5 2,8,6 2,8,7 2,8,8

1 2 43 5 6 07

1

2

3

4

2,1 2,2 2,3 2,4 2,5 2,6 2,7 2,8

1 2

2,8,8,1 2,8,8,2

What is the pattern of outer shell electrons across a period?

What is the pattern of full electron shells in a group?


Electron trends in the periodic table

Trends down a group:

The point at which a new period starts is the point at which electrons begin to fill a new shell.

The number of a group is the same as the number of electrons in the outer shell of elements in that group,except for group 0.

the number of outer shell electrons is the same;

the number of complete electron shells increases by one.

the number of outer shell electrons increases by one;

Trends across a period:

the number of complete electron shells stays the same.


Electrons and groups


Groups and periods


What’s the electron arrangement?


Names of groups in the periodic table


The Periodic Table




Summary activities

Arranging elements

Contents


Glossary

atomic number – The number of protons in an atom. Sometimes called the proton number.

electron arrangement – A shorthand way of writing the number of electrons in an atom’s electron shells.

element – A substance made up of only one type of atom.group – A column in the periodic table containing elements

with the same number of outer shell electrons and similar chemical properties.

period – A row in the periodic table containing elements with the same number of full electron shells.

periodic table – The table that lists all the elements in order of increasing atomic number, arranged into groups and periods.

property – Any characteristic of an element.


Anagrams


Matching elements and groups


Multiple-choice quiz

ks4 the periodic table (boardworks)

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